Apparatus for treating milk.



w.1. DAVIS a L. JOHNSON. APPARATUS FOR TREATlNG MILK. APPLICUON FILED DEC. 4. 1915.

Patented Aug. 14,1917.

3 SNEEYS--SHEET l.

E Exhaust W. l. DAVIS L L. JOHNSON. APPARATUS FOR TREATING MILK. APPucATmN min Dsc. 4. 191e.

1 236,548. Patented @55.14.1917.

" a SHEETS-sain 2.

W. 1. DAVES & L. JOHNSON.`

APPARATUSFOR TREATING MILK.

APPLICATION FILED Dic. 4. 191e. v'

Patented Aug. 14, 1917.

3 SHEETS-SHEET 3.

lparts A smaller chamber is formed on the top of the drum by the hollow, truncated, conical piece 37, which is preferably provided at its lower end with the inwardly directed annular flange 38, which is threaded into a suitable channel formed in the top of the disk 30. Extending between and through the disks'30 and 32 are aplurality,

six as illustrated, of tubes'39, which are preferably brazed in place, and form a plurality of passages between the top and bottom chambers of the drum. The disk 30, as seen in Fig. 6, has a plurality of small radial passagesV 4()- bored therethrough vand cooperating with an annular passage formed by the sleeve 41, which is secured in a suitable annular recess in the center 'of the bottom of the disk and extends down as shown, surrounding the tube'34. A number of openings 42, corresponding in number to the passages 40, connect said passages with the annular'passage formed between the sleeve 41 and the tube 34. The upper ch amber of the drum is preferably provided with a plurality of radial partitions 43, which are shown as in the form of triangles, and which are seated in suitable radial re cesses 44 formed in the interior of the bottom of the truncated conical piece 37. 'lhe main chamber of the drum is likewise provided with similar radial partitions 45,

ywhich are seated at their lower ends in suitable' radial,.vcrtica'l channels formed in the top of the disk 21, and are held in place at their middle portions bythe horizontal ring 46 secured on the inner wall of the drum 25, and forming an inwardly projecting Harige provided with a plurality of recesses 47 therein, with which cooperate the' portion of the partitions 45 adjacent 'to the notches 48 provided therein. The -outer downwardly. inclined portion of the disk 30, on the under side of which is formed the annular bearing surface 29, has formed therein a plurality of radial passages 49, which open at their inner ends to the horizontal annular passage 50 formed between the top of the conical, hollow drum 25 and the adjacent bottom of the disk 30. The annular passage 50 and the interior of the body of the drum 25 are connected by the annular passage 51 formed between the outside of the top of the cylinder 3l and the inside of the top of the conical drum'25. A ring 52 is preferably employed cooperating with the recesses 53 formed in thetop of the partitions 45 to aid in holding them in place. The upper portion 54 of the casing 20 has resting thereon the sheet-metal, annular casinglr 55, which has the inwardly and upwardly directed portion 56 which approaches thc to, of the drum 25, so that the milk discharged ecntrifugally through the passags 49 will How down on the upper 'surface of the flange 56 into the/annular trough 57l formed by the lower portion of the casing 55.. The top of the casinvis formed `by the dome-like sheet-meta cover 5S, which has at its periphery the annular groove 59 resting on the coperating curved top 60 of the casing 55. Secured on the 1nside of the casing 55 and forming, so to speak, a part of its inner wall, is an annular sheet-metal ring made up of the inwardly and upwardly inclined top portion (il, the

to the steam pipe 1l, and havingr the cock 66 .i

therein. Extending through the drum 64 is a pair of substantially semicircular passages G7, which coperate with similarly sha-pcd passages formed in the top of the drum 64 and in-the bottom of the cup 69 secured on the top of the drum G4. The steam entering the drum does not reach the passages 67, which are cut ofi' from the inv f terior of the drum, but passes around the walls' of said passages and to the center of the drinn, where it passes down through the vertical pipe 70 screwed in the center of the bottom of' the drum and extending down through the center of the tube 34, which has formed therein near the bottom of the tube 70 the inwardly and downwardly projectingl flange 71, which forms a sort of a nozzlc'to eoperate with the end of the tube 70 and form an injector for the steam. A plurality of holes 72 formed in the tube 34 permits the escape of the steam into the cylinder 31. The cup (lf) has sented in it a shallower cup 73, which has an aperture 74 leo f is closed by the body 75 of'a float Vvalve having the tapering stem 7G (hereof coperating with the'nomle of the cock 77 secured on the end of the pipe 7S through which the milk delivered.

Associated with van auxiliary fraine 79 is a tank S0, which preferably takes the forni of a vertically elongated cylinder, with the sleeve Sl, closed at'its top and bottom, se cured centrally in the top thereof. Apertures 82 formed in the top of the sleeve Sl permit air-to pass from the top of the tank 80 into the sleeve Sl; A pipe 83 extends from the bottoni of the sleeve 8l down toward the bottoni of the tank 80. 'An overflow pipe 84 has its upper cud near the bottom of the sleeve 81, while its other end passes through the bottoni of the tank 80 and may be carried to any convenient point i y 102 has the'pipe 105 leading to the holder and the pockets formed `by the radial .parti- 'no which, inside of the tank, is continued in the hollow drum 31.. Here the steam is con- `.134)

.65 mosphere. A discharge pipe 117 for the The pure water d of condensation flows out 130 of discharge, such as an adjacentsewer. A water of condensation in the drum is concock may be interposed in this pipe. nected to the interior of the annular casing The exhaust Vsteam from the turbine 13 .61, 62 and 63, #and passes out through a suitpasses through an enlarged pipe 86 into a able recess 118 formed in the upper portion 6 still larger elongated cylinder 87 secured of the wall of the cover casing 55, so that 7 on the top of the frame 79. At theother the parts can be readily assembled and taken end of the cylinder is a reduced pipe 88', apart for cleaning. The turned-down end which will be carried to wherever the steam 119 of the pipe 117 dischar es the water of is to be exhausted. .Adjacent to the cylinder condensation into the funne 120 secured on le 87 is an air pump 88, which pumps air in the upper' end of the' p'pe 121, preferably ,5 'through a suitable strainer 89, located out provided with a cock 122 and opening into of doors, and through a pipe 90, to the inthe side of the tank 80 at 123. let port of the pump 88, which is prefer- The operation of the completeapparatus ably operated by a rotating shaft 91 carrying `is as follows: 15 a-sprocket-wheel 92 connected yby a sprocket rlhe milk to be clarified, purified, aerated s. chain 93 with a sprocket pinion 94 secured and heated is delivered into the cup 73 on the horizontal shaft 95 journaled in a through the pipe 78, the-valve 75 coperatbearing formedin the Wall of the .casing 20. ing with the aperture 74' in the bottom `of 0n the inside of the casing is a bevel wheel the cup serving to regulate the flow of the 2e 96 secured on the shaft 95 and meshing with milk and prevent its entering more rapidly a5 the bevel pinion 97 secured on the vertical than the apparatus can dispose nof it. The shaft 98, whichhas the spur gear wheel milk flow-ing through the aperture 74 passes 99 thereon meshing with the spur gear pindown through the channels 67 and into the ion 100 secured on the shaft 15, so that the upper chamber of the drum, the eccentric 25 turbine, through the gearing described, also location of the channels 67 beingnecessary vn serves to drive the vair pump 88. There to discharge the milk into the annular chamthe milk is to be delivered at a point above ber in the top of the drum, from which the the bottom of the cover casing 55, the shaft milk passes down through the passages 95 is provided with a Worm 101 rota-ting in formed by the tubes 39 to the bottom ofthe the casing 102, which is connected at one lower chamber, tl'iefouter wall of Whichis 95 end bythe pipe 103 with the pipe 104 conformed by the ltruncated conical casing 25. nected tothe bottoni of the cover casing 55, As the entire drum kis rotated rapidly, the and from which the clarified and heated milk milk is hurled by centrifugal actlon `to `the is delivered. The other end of the casing peripheries of both the yannular chambers or wherever the milk is to be delivered. tions 43and 45 serve to collect the `solid im-l The discharge outlet of the air pump 88 is purities which may be ,present in the milk. connected to a'k pipe 106, which is passed The milk in the outer and lower chamber' of into the interior of the sleeve 87 and is given the drum passes up and through the pass a few helical turns through the sleeve and sages 51, 50 and 49, and is 'discharged tan- 105 emerges adjacent the tank 80, where a verti` gentially outward againsty the under `side cal portion 107 of the pipe leads up above of the annular Bange 62. The heatedl air the top of the overflow pipe 84 and enters subsequently referred to fills the `annular the side of `the tank 86, and a yportion 108 chamber. formed within the cover 55, and 5 thereof continues downto the bottom of the the hot milk thus sprayed through the im tank where it is provided with a horizonwashed and heated air is thoroughly aerated,

tal dischar e portion 109 having suitable and any disagreeable odors that-itma have apertures t erein. Secured in the center arecarried oli' by the washed and cated of the sleeve 81, and extending upward air risingthrough the discharge outlet 116. 5g from near the bottom thereof, and passing At the same time, with the cock 66 open, `115 out throughv its top, is the pipe 110, which the steam from thepipe 11 passes through the through an extension 111 passes down topipe 65 into the interior of the drum l64fand ward the bottom of" the tank 80, which it down through the pipe 70, and out through enters through the horizontal portion 112, the apertures 72 in the tube 34, and into the helical portion 113, extending below the densed as its heat is `extracted by the milk level of the overflow pipe 84. Above this `flowing through the pipes 39, and it eventu pipe 84, the helical portion 113 is continued ally fills. the drum and passes up through through the `Straight portion 114, which the annular passage between the sleeve 41 30 passes out through the top of the tank 80, and the tube 34, through the aperture 42, 125 and is led through the horizontal portion and out throughvthe passages 40,'this Wa- 115 into the top. of the cover casing 55 and ter of condensation thus collecting in the opposite the larger discharge pipe 116 leadannular channel or receptacle formed `by ing from the top ofy the casing to the at- `the annular sheet-metal piece 61, 62, 63.

` the tubes 107 and 108,

` tank 80, and inward through the pipe 117, and is carried bythe pipe 121 into the bottom of the tank v80, where it is employed to heat and wash the air passing through 4the water in this tank. As previously noted, cold air from the outside is pumped in through vthe strainer 89V, pipe 90, and by the pump 8S is forced through the pipe 107, where, in passing through the sleeve S7, the exhaust steam serves to heat the air and increase its temperature, This heated alr, passing through the tube '109 into the water accumulated in the bottom of the tank 8O below the. top of the overflow pipe 84, and rises through the heated. water, being thoroughly washed and further heated in the process. Escaping from the water, it passes up tothe top of the through the apertures 82 to the sleeve S1, and down to the bottom of said sleeve, whence it escapes up through the pipe 110, whence it is carried by the pipes 111 and. 112 to the helical pipe 113 within the water of condensation, where it more thoroughly heated, and tempered, and passes from the tank 80, through the pipe 114,-to the cover casing 55 at any1 desired temperature, such, for instance, as the purifying and clarifying temperature. This air pumped through the pipe 115 into one. side of the casing 55, flows freely in bothdry rections around the interior ofthe casing to the discharge outlet 11G, aerating and purifying the milk and carrying oft any undesirable odorsI in its passage.

Vhile we have shown and described our invention as embodied in the form which we at present consider best adapted to carry out its lun'poses, it will be understood that it is capable of modications, and that we be limited in the inter pretation of the following claims except as may be necessitated b v the state of the prior art. What we claim as new, and desn'e to Ysecure by Letters Patent ofthe United States, is;

1. In apparatus of the ela ss described, the

combination with. a rotating member serving to propel a thin sheet or spray of liquid, of means for heating said liquid before it is 'thus propelled, an inclosed aerating chamber in which said liquid is propelled in a thin sheet or spray, and means for delivering heat-ed air to said chamber.

2. In apparatus of the class described, the combination with a rotating bowl having passages from which thin sheets or sprays of liquid may be driven, of means forheating said liquid while it is traversing the passages, an inclosed annular'aerating passage into which said liquid is discharged, and means for delivering heated air to said annular aerating passage.

3. In apparatus of the class described, the combination with a rotating bowl, of a is discharged from steam chamber therein, milk passages leading through the steam chamber to' the bowl, and means for supplying steam to said chamber.

4. In apparatus of the class described., the combination with a rotating bowl, of a steam chamber therein, milk passages leading through thc steam chamber to the bowl, and means for supplying steam to said chamber, said means consisting of a stationary pipe 4extending down into the center of the bowl, and a central perforated pipe into which it discharges, the perforations opening into the steam chamber. v

5. In apparatus of the class described, the combination with a casing, of a vertical spindle journaled therein, a centrifugal bowl carried by the spindle, an annular collection chamber into 'which the bowl discharges, a rotary pump, gearing connecting the spindle and pump shaft, and a delivery pipe connecting the collection chamber and the pumpr easing.

G. In apparatus of the class described, the combination with a casing, of a vertical spindle journaled therein.y means for rotating said spindle, a centrifugal bowl` carried by the spindle, an annular collection chamber into vwhich the bowl discharges, a horizontal .rotary pump-casing, an operating shaft therein, a bevelwheel on the inner end of said shaft, a bevel gear meshing with said bevel wheel, a spur gear secured to the bevel gear, and a spur gear pinion secured "on the vertical spindle meshing with the spur gear wheel.

7. In apparatus of the class described, the combination with a casing, of a bowl mounted to rotate therein, a steam pipe discharging into the center of the bowl, an annular milk-receiving chamber, a disk-shaped steam chamber on the top of the steam pipe having eccentric milk passages therethrough, a double-bottom milk receptacle on the steam chan'iber having openings in its lower bottom registering with the eccentric milk passages, a central passage in the upper bottom, a discharge nozzle above the milk receptacle, and a float cooperating with the nozzle and with the central passage, substa ntially as and for the purpose described.

8. In apparatus of the class described, the

combination with a bowl and means for roacepta y at the .to of 'the bowl, pipes extending through t e steam chamber and connectin v the lannular milk receptacle and the bow proper, dischai e passages from the top of 5 the bowl for te milk, discharge passages l from the top onf the steam chamber for the water of condensation, and annular collecting basins coperatin with said assages. In apparatus o 'the class ascribed, the combination with al rotatin l a centrifugalbowl thereon, and` a plurality oi radialribs projecting' inwardly fromthe walls of the bowl, for `thepur ose described. 11.111 apparatusl of they` c ass described, the combination with a rotating spindle, of la centrifugal bowl therein havingl a pluralityof radial ribs` projecting inwardly from" the' walls thereof, a' receiving bowl aibriwe.V the" c'entrifuglal bowl likewise provided'with a plurality of radial ribs proyect- Ving inwardl vfroniits walls, and passages connecting t e two 12.111 apparatus of the class described, the'conihiiiation with a rotating spindle, of g:- lva"eent'zrifug'al-'bowl therein hav-ing a lurality offradiial ribs projecting inwardly rom the 'walls'y thereof, a receiving bowll above the centrifugal bowl likewise provided with a. :f plurality of radial ribs pro1ectngv inwardly spindle, of.

5g f romits'walls, passages connectin the two I-bewlsafa steam chamber surroun `ing said passa es, and `means for'supplying steam' to thee-amber.

"13. Infapp'aratus of theV class described,

, sechste' bien@ witherotatng bowl P-fo @vided with'meIIS. l t

` for discharging -milk 'tlxelfiefrdni` centrifugall of means for passing4 afheatin Wrm the? mi k passing therethrough witheV utfcommingling therewith. y 4

. 14, In apparatusy of the class described,

the combination with a rotating bowl, of a Lcollecting'annulus for milk'dischai'ged therefrom-=eentrfugally, means fonpassing a healtin i fluid through said bowl to warm the iii'` kfpassingtherethrough ,v vithoutv comininlngtherewith, and. another Vcollecting *taniiulus yjor the centrifugallydischarged hectnpilud. i f apparatus` otjthe lclass described, lie-'combination with a. .main bowl having nti'ifugal dischargeipassagesrfrom the top thereof, of an' auxiliary bowl above the main bowl and' rotatin therewith, a heating-Huid cylinder within he main bowl, pipes assing `fiom, the bottom-cf ,the auxiliary owlthrough the heating-fluid cylinder and openfug into the bottojino the main bowl, 'and4 ymeans for supplying the heating-duid cyl- BK!` indergwithfheating fluid.`

llnapparatus of theA classv described, the combination with a main bpwl having centrifugal discharge passa y es from the top thereof, of an auxiliary loovrl bove the main lthrough. the auxiliary bowl, and

'the combination with necting the pump with 'the annular chamber fluid-.t rough said .bowl to l vided with means vided with means cylinder within the main bowl, 'ipes assn from the bottom of the auxi iary owl through lthe heating-Huid cylinder and'opening into the bottom of the" main bowl, and means for supplying Vthe heating-fluid cylnder with heating iiuid, said heatin -fluid cylinder being provided with centrifugal discharge passages.

v17. In apparatus of the class described, the combination with a main bowl having centrifugal discharge passages from the top thereof, of an auxiliary bowl above the main bowland rotating therewith, a heatingLiluid "cylinder withinjtlie main bowl, pipes ass- -ing from the bottom of the auxiliar owl through the heating-fluid cylinder an open ing into the bottom of the main bowl, a pipe leading from the heating-fluid cylinderup a smaller stationary pipe extending down inside the rotating pipe'into the heating-duid cylinder. 18. In apparatus of the class described,

va rotating bowl pro.- vided with means for discharging milk l therefrom centriiuglly, Q-a chamber ,into 90 which themilkis sprayed by centrifugal action, and means for forcing a current of air through said chamber to aerate the milk. 19. In4 apparatus of the class described, the combination with a rotating bowl pro,- vided with means for discharging v milk therefrom centrifugally, of au annularchamber into whichthe milk is sprayed by centrifugal action, an air pump, and pipes con'- so that a current of air can be forced through said chamber to aerate the milk. p i 20. In apparatus olf the class described,

the combination with a rotatingv bowl proor discharging milk ther'efron'i .centrifugally, of a chamber into .which-:the milk is sprayed by centrifu al action, a wash-water. tank, and means or orein a. supply of air through the water in sai tank and thence to 4the chamber to 1,10 aerate the,

21. In apparatus of thev class described, the vcombination with a rotating bowly proor discharging milk therefrom 'centrifugally, of means for pass- 115.`

ing aheating fluid through said bowl to warm the mi k without commin ling therewith, a chamber into' which t e milk is sprayed by centrifugal action, and means for forcing a current yolf chamber to aerate the heated milk.

22. In apparatusofthe class described, the combination withV a rotating bowl provided with means for discharging milk therefrom j centrifugall ing a heatin 'fluid t rough saidbowl to passing theethrou h without commingling therewith, a cham Y r into V Ywhich the is sprayed by centrifugal action, a wash-water tank, and means or 130 air through said of means for pass- 4125 i 'B i vforcing a supply of air,y through -thejwater in the.tank and through the chamber to aeratethe heated'milk. 23. In apparatus of the class described, the combination with a rotating bowl provided with means for discharging v:milk therefrom centrifugally, of means for passing' a lheatin fluid 'through said bowl to Warm the mi k passing therethrou h yvith' out comminglng therewith, a cham er into which the milk is sprayedA by centrifugal' action, a wash-water tank, means for forcing a supply of vair through the Y, water in the' tank and through the chamber vto aerate ,15 the heated milk, a"collec ting. chamber into which the'heating fluidvi's discharged after passing through the bowl, and av pipe leading from the heating-Huid collecting-cham'- ber to the wash-water. tank.

24. In apparatus of the class described, the kcombination with a spindle', of a base disk secured thereon, an outer conical cylinfder' on thc'fbase-disk, a cover-disk fon/the conical cylinder, an inner. cylinder-secured ,25. to the bottomof'the cover disk, land .a base 'disk for the inner cylinder having an eX-v A tension screwed into the lbase disk..

25. vIn apparatus ofthe class described, the combination with'abspindle, of a base disk secured thereon, ani outer conical cylinder` on the basevdisk, a cover disk for the .conical cylinder, an inner cylinder secured Ilto the bottom of the cover disk,-a base disk l for the inner. cylinder having an extension f5-screwed iitothe base disk, and `a conical A supplemental bowl secured 'on top of the cover disk. i i l 'y 26. In apparatus of the class described, vthe combination with a spindle, 'of a base 4o disk secured thereon, an outer conical'cylin- 'i der on the basev disk, a cover disk for the conical cylinder, an inner-cylinder secured. toy the bottom of Athe cover disk, a base disk forV the innercylinder having an extension 5 screwed into'the base disk, a conical supplemental bowl' secured on top of the cover disk, and a plurality of tubes extending" through the :over disk. and thebase disk for the inn, cylinder so as to furnish' pas,

' r5o sages fron the supple1n.ntal' bowl to the bottom of tlnl niain howl v ,g 27. In aA paratns of the class described, the combination with' ai'spindle, lof a base disk secured thereon, an outer conical cylin- 'Bder on the base disk, a cover disk for the conical cylinder, an inner, cylinder secured yto the bott-emot the coverdisk, a basev disk v `for-Lne innerl cylinder having anpxtension screwed into the base disk', a conical supple-- v80 mental4 bowl secured on top` of the cover disk, a plurality of tubes extending through,` the cover disk andthe base disk for the innerv cylinderV so as'fto.. furnish passages from the supplemental b w1 to `the bottoni `55 oLthc .nain bowl, anda heating-fluid supspirulle tothe air'pump, ,a convolute .pipe extending from the pump;through'thev l ply pipe extending downA through the auztil iary bowl andthe cover disk andzinto the inner cylinder.

2S. In `apparatus of the class described the combination'with a rotatin bowl ci un annular casing into which t c milk is discharged 'centrifugally,a .shaft for the bowl, an air ump, gearing for driving the pump from e shaft, and pipes connecting the air pump with the annular casing to deliverairthereto to aerate the milk.

29. In apparatus of the class described -the- 'combination with a 'rotating bowl of an annular casing .into which the mil is .discharged centrifugally, a shaftfor the bowl, an air pump, pipes connecting the air pumpwith the annular casing to deliver" air to said casing to aerate -the milk, a pipe leading from the ,annular casing a milk pump connected with the pipe, an "gearing connected with the 'shaft for driving bot pumps.

50..1n apparatus of the class described, the combination with a rotating bowl, of an annular casing into which the' milk is discharged centrifugally, a shaft for the bowl,

an air pump, pipes connecting the -air pump with the annular casing to deliver air-fo said casing to aerate the milk, a pipe leading from theannular casing, a milk pump conf `nected with the pipe, and gearing connected with theshaft for driving both pum s,=said gearing consisting of a spur gear W eel onA4 the shaft, a spur gear wheel meshing therewith, a bevel pinion secured to the spur gear wheelfa hcvelwheel secured on the shaft of thev lnilkpump, a .sprocket wheel secured on the same shaft, a sprocketwheel on the shaft of the pump, and a s rocket chain connecting the sprocket whee s.

3l.. Inl apparatus of theclass described, the combination with a rotating bowl of an annular collecting chamber, a spindle on which the bowliis mounted, a' steam turbine secured to the spindle, a'n exhaust ipe for the turbine, an air pump, gearing rom the spindle to the air pump, a convoluted airpipe extending from the pump through the exhaust pipe, and pipes leading from the convoluted ail-'pipe Ato the annulancollecting' chamber.

In apparatus of the elassdescribed, the combination with a rotating bowl lof an annular collecting chamber, a spindle on which the bowl is mounted, a steam turbine secured to the spindle, an exhaustpip'e for the turbine, an air pump, gearing from ,the

air

exhaust pipe, a' water-tank, a pipe leading from the convoluted air pipe'to the bottom of the -water tank, and 'a pipe from the topV "f the' Water tank to the annular collecting chamber.V 1 1 the combination with a rot-ating bowl, of an annular collectlng chamber, a spindle on which the bowl .is mounted, a steam turbineV serun'i'ad to the spindle, an exhaust pipe for nthe turbine, an air pump, gearing from the spindle to the au' punni. a, convoluted air' pipe extending from the pump through the exhaustpipe, pipes leading: from the convoluted air pipe to the annular collecting chamber, a Water tank', a pipe coiniccting the convoluted air pipe with the bottom ot' the' water tank, a convoluted pipe in the water tank connected with the top thereof, and. a pipe connecting the convoluted pipe to the annular collecti ng chamber.

34.. In apparatus of thc class described,

i the combination with a rotating bowl, ol. an

annular collecting chamber, a spindle on which the bowl mounted, a steam turbine secured to thc spindle, an exhaust pipe for the turbine, an air pump, gearing from the spindle to the zur pump,` a convoluted air pipe extending from the pump through the exhaust pipe, a water tank', a, pipe leading from the coIWOluted air pipe to the bottom of the water tank, a pipe from the top of the water tank to the annular collecting chamber, ineanswithin the bowl for applyinol heatingI fluid thereto, an annular chamber associated with the bowl to receive the waste heating fluid, and pipes leading from the annular waste-luid chamber to the tank.

-i. 'In algiparatus of thc class described,

the combii'iation with a` centrifugal bowl, of

f' a. collecting annulus tl'ierefor, .means for r0- 'tatng the bowl, an air pump, a tank into the bottom of which the air pump discharges, a coil in the bottom of the tank, a pipe connecting said, coil with the top of the tank, and a pipe from' he coil to the collecting` annulus.

3G. In apparatus of the class described the combination with a centrifugal bowl, of a collecting annulus therefor, means for r0- tatine the bowl, an'air pump, a tank into the bottom of which the air pump discharges, a coil in the bottom of the tank, a. pipe ounce-tingr said coil With the t0 0f the tank, a pipe from the coil to the co ectintor annulns, means ilor supplying heating fluid to the centrifugal bowl, a collecting annulus for the Iexhaust heating fluid, and a. pipe cimncctng the heating-fluid collectingannulus with the tank.

3T, In apparatus ot the class described, the combination with a rotating bowl provided with therefrom, of a waslrwatcr tank, means for` supplying the same with distilled Water, and means for forcing a supply of air through the water in said tank and thence over thc mill; acted upon by the bowl.

In witness whereof, we have hereunto setv our hands and allixcd our seals this 23rd day of November, A.. l). 1916. 

